Automatic Table Top Refractometers

[Features][Specifications][Applications][process refractometer]

Features of Automatic Refractometers

• Quick readout
• Fully Automatic - simply load a small sample and press one button.
• Digital readout of refractive index, Brix and sample temperature.
• Temperature compensated Brix readings for samples from 15 to 40 Degs C.
• Only a small volume (0.3ml) sample needed
• Many optional configurations for temperature control and automatic sample handling.
• RS232 data port.
• Built in diagnostics

Introduction to Automatic Refractometers

Refractometers are widely used to measure the amount of dissolved substances in solutions containing mainly sucrose. The relationship between refractive index and the amount of dry substance content is well known for sucrose and is the basis of the Brix scale which is measure of the number of grams of sucrose present per 100 grams of aqueous sugar solution. (50 Brix means 50 grams of solid per 100 gms of solution) This relationship holds for a large number of similar substances and so the Brix scale is widely used in the food industry. Unfortunately the refractive index of a sugar solution changes with temperature while its solid content remains the same. ( The same refractive index at different temperatures correspond to different Brix values.) Manual "Abbe" refractometers do not compensate for this temperature effect and manual correction tables should be used to adjust the readings to a standard temperature.

The Schmidt and Haensch range of automatic refractometers supplied by Topac measure both the refractive index and the temperature of the sample in order to evaluate the Brix value. They read out both the actual refractive index and the actual sample temperature, but they automatically correct the Brix value to what it would be at 20 degs C. regardless of the actual sample temperature. ( In the range 15 - 40 C)
The instruments come in a variety of configurations to meet the needs of laboratory , QC, research and production applications. If you don't see what you need here then please call us to discuss your application.

The ATR C instrument (pictured above) incorporates the sample holder into the same case as the electronic console. The sample (0.3ml) is easily placed in the funnel shaped sample well which is easily removed for cleaning. Brix reading are automatically compensated to 20 deg C. in the temperature range 15 -40 degs C. An optional temperature stabilized sample holder can be fitted to the ATR-C. This facilitates adjustment of the measuring temperature in the range +15 - + 40 degrees Celsius with the aid of temperature controlled circulation bath.

The ATR-E is similar to the ATR-C above. It is designed for routine daily use for Brix measurements with an accuracy of 0.1 Brix with a fixed sample holder. (There is no temperature controlled sample holder for the ATR-E)

The ATR S is a continuous flow through version of the above, for use as a cane sugar purity analyzer in combination with the SACCHAROMAT polarimeter. This unit includes a stainless steel flow through cell, vertical prism and RS232 interface.

Model ATR-SW with external sample holders
The ATR SW is more accurate refractometer having a resolution of 0.0001 refractive index and 0.02 Brix. The sample holder is external to the electronic unit and can be used in either the horizontal position or in a vertical position with a flow through cell and funnel. The sample holder is fitted with recirculating temperature control circuit for stabilizing the sample temperature with recirculating fluid from a temperature controlled bath. The sample door used in the vertical flow through version may also be hooked into the temperature control circuit providing a highly stable thermal mass all around the sample. The vertical mode of operation is very useful for monitoring a continuous flow of sample liquid. In this case the electronics can be set up to make measurements at predetermined intervals from 1 to 99 seconds. The vertical orientation is also useful for samples where solid particles may settle during measurement - in the vertical mode such particles do not settle on the measuring prism.

 pdf brochure
Model DUR-SW High Resolution Research Digital Refractometer
The DUR SW is a more sophisticated digital table top unit than the ATRs above. It offers a very high precision with a resolution of 0.00001 refractive index and 0.01 Brix . The more powerful electronics unit makes it possible to store up to 30 different scales and allows you to program scales to suit your own requirements. Optional scales include Brix, Oechsle, Beaume, Serum, Protein etc. The display includes 8 lines of 30 characters each and the software provides for sample identification, clock, and print out configuration. The layout of the display can be changed by the user. The sample holder provides for horizontal or vertical use as described for the ATR-SW above. In addition the DUR electronics can work with an additional refractometer head. ( The refractometer heads can also be controlled by our Polarimeters ) for combine POL and BRIX measurements

Model DUR-W2 Full Abbe range
The DUR-W2 is similar in electronic capability to the DUR-SW but with the ability to cover the full Abbe refractive index range from 1.33000 - 1.70000. .

Model DUR-HT High temperature refractometer
The DUR-HT is a full Abbe range refractometer designed to work with samples requiring higher temperature - up to 80 degrees C. The sample holder temperature is maintained at the desired temperature by using a circulating fluid temperature bath. The detector and electronics are cooled by a separate water cooling circuit.